Please refer to FIG. 1. FIG. 1 is a diagram illustrating movement restriction of a conventional multimedia interactive system 100. The multimedia interactive system 100 comprises a display device 110 and a pointing device 120. The pointing device 120 can be, for instance, an air mouse, a remote controller, a control handle of a gaming console or a laser pointer, etc., for controlling a cursor displayed on the display device 110. For instance, the cursor displayed on the display device 110 moves according to orientation, direction and distance of the movement of the pointing device 120. Accordingly, the display device 110 also displays movement trajectory and position-after-movement of the cursor according to such movement of the pointing device 120. Further, a position of the pointing device 120 can be represented by factors such as yaw angle, pitch angle and roll angle in a three-dimensional (3D) spatial reference frame.
In FIG. 1, an initial position of the cursor is set to be L1′ and an initial position of the pointing device 120 is L1. When the pointing device 120 moves towards right to a position L2, the shift is S1. The shift S1 will lead the cursor to make a shift S1′ and the cursor reaches a border (i.e. position L2′) of the display device 110. When the pointing device 120 continues to move towards right to a position L3, the shift is S2, but the cursor cannot continue to move towards right accordingly since the cursor has already reached the border of the display device 120, so the cursors stops at the border of the display device 110 (i.e. the cursor remains at the position L2′).
Afterwards, the pointing device 120 then moves back (i.e. moves towards left) to the position L2 and the shift is S2. The shift S2 will lead the cursor to make a shift S2′, so as to move from the position L2′ to a position L3′. The pointing device 120 then moves back (i.e. moves towards left) again to the initial position L1 and the corresponding shift is S1. The shift S1 will make the cursor to perform shift S1′ so the cursor is moved from the position L3′ to the position L4′. Although the pointing device 120 moves towards right at first then moves towards left to get back to the initial position L1, the cursor cannot get back to the initial position L1′ due to restriction of the border of the display device 110. In other words, in the conventional multimedia interactive system 100, a maximum limit exists for shift of the pointing device 120. If the maximum limit is exceeded, reset/recalibration is needed to restore the interaction between the cursor and the pointing device 120 back to normal.
Please refer to FIG. 2A and FIG. 2B. FIG. 2A and FIG. 2B are diagrams illustrating rotation restriction of the conventional multimedia interactive system 100. FIG. 2A illustrates when the rotation of the pointing device 120 is within a permissible range and FIG. 2B illustrates when the rotation of the pointing device 120 is out of the permissible range. In FIG. 2A, a rotation angle S3 of the pointing device 120 is within the permissible range, so the cursor displayed on the display device 110 makes a shift S3′ accordingly. In FIG. 2B, a rotation angle S4 of the pointing device 120 exceeds the permissible range, so although the cursor displayed on the display device 110 moves accordingly, but the cursor will stop at the border of the display device 110 due to restriction of the border of the display device 110. More specifically, the pointing device 120 continues transmitting signals of moving outwards, for the cursor to move outwards continuously, but due to restriction of the border of the display device 110, the cursor appears to be stationary to the user. For instance, the pointing device 120 can be a laser pointer. In FIG. 2A the later pointer points to the display device 110, for controlling movement of the cursor accordingly. In FIG. 2B the laser pointer points in a direction away from the display device 110, hence the permissible range is exceeded for the cursor to appear to be stationary.
Please refer to FIG. 3A and FIG. 3B. FIG. 3A and FIG. 3B are diagrams illustrating region restriction of the conventional multimedia interactive system 100. FIG. 3A is a diagram illustrating when an operating range of the pointing device 120 is within a permissible region. FIG. 3B is a diagram illustrating when the operating range of the pointing device 120 is beyond the permissible region. In FIG. 3A, the pointing device 120 makes a shift S5 in a permissible region A, hence the cursor displayed on the display device 110 also makes a shift S5′ accordingly. In FIG. 3B, the pointing device 120 is changed to operate in a region A′ which is beyond the permissible region A. Hence in FIG. 3B the shift S6 of the pointing device 120 in the region A′ cannot lead the cursor displayed on the display device 110 to move accordingly, and the cursor can only stop at the border of the display device 110. For instance, the pointing device 120 can be a laser pointer. In FIG. 3A the laser pointer is in front of the display device 110 so the cursor can be controlled with the laser pointer. In FIG. 3B a position of the laser pointer is far away from the display device 110, hence the permissible range is exceeded and the cursor cannot be controlled by the laser pointer.
Therefore as described above, in the conventional multimedia interactive system, operation of the pointing device encounters a lot of restrictions, causing inconveniences.